A：封建军阀垮台
B：民主共和观念深入人心
C：资产阶级共和制度适合中国
D：帝国主义在华寻找代理人的政策破产
用一个平面去截一个几何体，如果截面的形状是长方形，则这个几何体不可能是（ ）
A. Let's go.
B. Are these your shoes?
C. Let's play football.
D. They are on your feet．
E. What are they?
A：It's warm today．____
B：Great!____
A：Where are my shoes?
B：____
A：No．they aren't．
A：Look!____
B：Oh．I'm sorry．
It's time _______ school.
